This application requests funds for a single major piece of equipment - an EPICS 751 fluorescence activated cell sorter (FACS) system. This instrument will be used to establish a shared flow cytometry research service center at LSU Medical Center which will be operated to enhance the progress of biomedical research at LSUMC. The level of PHS-supported research by the faculty at the LSU Medical Center has increased significantly over the past several years. However, the Medical Center still does not have the needed facilities to carry out research in many of the most important aspects of modern cell biology and biochemistry. To address this problem, the institution has established a mechanism (Core Laboratories) to promote and encourage acquisition and shared usage of instrumentation. A "Synthesis" Core in the Department of Biochemistry and Molecular Biology has been established with previous SIG funds and now provides oligonucleotide and peptide synthesis to the LSUMC community, as well as a gas-phase sequenator facility. Similarly, we now propose to establish a Flow Cytometry Core built around commercial FACS instrumentation. Due to the cost of this instrument and to its specialized nature, it is necessary to seek funds for the FACS in a group effort such as this proposal and to make the cytometer available as a research service. The great strides in molecular biology made possible by the availability of recombinant DNA and hybridoma technology are now being translated into an increased understanding of cell biology and regulation. FACS instrumentation is essential to this effort since it facilitates the phenotypic analysis of individual cells and permits their selection on the basis of phenotype by sorting for detailed biochemical studies. In fact, as noted by each major user below, to carry out much of the research at the forefront of several fields, a capability in flow cytometry is required. It is the goal of this proposal to provide a center capable of carrying out state-of-the-art flow cytometric/sorting analyses. This will enhance significantly the progress of several research projects currently funded by the PHS/NIH at LSUMC. Moreover, biomedical scientists at the Center will no longer be hindered in carrying out their research.